Industrial valves - Multi-turn actuator attachments (ISO 5210:2026)

This document specifies the requirements for the attachment of multi-turn actuators to valves.
Throughout this document, “actuator” can be understood as “actuator” or “combination of actuator with gearbox” providing a multi-turn or linear output.
This document specifies:
flange dimensions necessary for the attachment of actuators to industrial valves [see Figure 1 a)] or to intermediate supports [see Figure 1 b)];
those driving component dimensions of actuators which are necessary to attach them to the driven components;
reference values for torque and thrust for flanges having the dimensions specified in this document.

Industriearmaturen - Anschlüsse von Drehantrieben für Armaturen (ISO 5210:2026)

Robinetterie industrielle - Raccordement des actionneurs multitours (ISO 5210:2026)

Le présent document spécifie les exigences de raccordement des actionneurs multitours aux appareils de robinetterie.
Tout au long du présent document, le terme «actionneur» peut être compris comme «actionneur» ou «combinaison d'un actionneur avec un réducteur» fournissant une sortie multitours ou linéaire.
Le présent document spécifie:
les dimensions des brides nécessaires pour le raccordement des actionneurs aux appareils de robinetterie industrielle [voir Figure 1 a)] ou aux supports intermédiaires [voir Figure 1 b)];
les dimensions des éléments d'entraînement des actionneurs nécessaires à leur accouplement aux éléments entraînés;
les valeurs de référence du couple et de la poussée pour les brides ayant les dimensions spécifiées dans le présent document.

Industrijski ventili - Priključki vrtilnih pogonov na ventilih (ISO 5210:2026)

Ta dokument določa zahteve za priključitev večobratnih aktuatorjev na ventile.
V tem dokumentu se izraz "aktuator" lahko razume kot "aktuator" ali "kombinacija aktuatorja z zobniškim prenosnikom" (gearbox), ki zagotavlja večobratni ali linearni izhod.
Ta dokument določa:
- dimenzije prirobnic, potrebne za priključitev aktuatorjev na industrijske ventile [glej sliko 1 a)] ali na vmesne nosilce [glej sliko 1 b)];
- tiste dimenzije pogonskih komponent aktuatorjev, ki so potrebne za njihovo priključitev na gnane komponente;
- referenčne vrednosti za navor in potisk za prirobnice, ki imajo dimenzije, določene v tem dokumentu.

General Information

Status
Published
Public Enquiry End Date
02-May-2025
Publication Date
06-Apr-2026
Technical Committee
TLP - Pressure vessels
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
16-Mar-2026
Due Date
21-May-2026
Completion Date
07-Apr-2026

Relations

Effective Date
01-May-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026
Effective Date
04-Mar-2026

Overview

FprEN ISO 5210 / ISO/DIS 5210:2025 - Industrial valves - Multi-turn actuator attachments defines the mechanical interface between multi-turn actuators (and/or gearboxes) and industrial valves or intermediate supports. Published under CEN/ISO cooperation, this draft standard specifies flange dimensions, driving/driven component geometry, and reference torque and thrust values for standardized actuator-to-valve attachment.

Key topics and technical requirements

  • Flange dimensions and layout
    • Defines standard flange types (F05 … F60) with prescribed diameters, bolt holes, spigots/recesses and minimum landing areas.
    • Hole positions are equi-spaced and located off‑centre according to specified angles.
  • Maximum torque and thrust
    • Provides reference maximum simultaneous torque (Nm) and thrust (kN) per flange type (Table 1). Examples: F10 = 100 Nm / 40 kN; F40 = 10 000 Nm / 1 100 kN; F60 = 40 000 Nm / 4 000 kN.
    • Values are based on bolts in tension at 290 MPa and a friction coefficient of 0.2; Annex A explains calculation assumptions.
  • Driving and driven component dimensions
    • Prescribes dimensions for actuator driving components and valve driven components (Groups A–D for combinations transmitting torque and/or thrust, plus provisions for linear actuators).
  • Bolting and tolerances
    • Bolting clearances reference ISO 273; hole diameters and tolerances (e.g., f8 for spigot) and nut/head landing rules are specified.
  • Designation and documentation
    • Flanges are designated by flange type (F05–F60); the standard includes normative Annex B on keys/keyways and informative Annex A on calculations.

Applications

  • Ensures mechanical compatibility between actuators and valves across manufacturers.
  • Used for specification, procurement and design of:
    • Rotary and multi‑turn actuators and gearboxes
    • Valve bodies and intermediate supports
    • OEM assemblies in oil & gas, power generation, water treatment, chemical and process industries
  • Helps sizing and selection by providing reference torque/thrust ratings and flange interfaces to avoid overloading fasteners or interfaces.

Who should use this standard

  • Valve manufacturers and actuator suppliers
  • Mechanical design and piping engineers
  • Procurement/specification authors and system integrators
  • Test laboratories and conformity assessors

Related standards

  • ISO 273 (fastener clearance holes) - normative reference in ISO 5210
  • Other valve/actuator interface standards and valve product standards (refer to the standard’s bibliography for specifics)

Using FprEN ISO 5210 / ISO 5210:2025 improves interoperability, simplifies procurement, and reduces engineering rework by standardizing the valve-actuator interface, flange geometry, and reference torque/thrust ratings.

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SIST EN ISO 5210:2026

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Frequently Asked Questions

SIST EN ISO 5210:2026 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Industrial valves - Multi-turn actuator attachments (ISO 5210:2026)". This standard covers: This document specifies the requirements for the attachment of multi-turn actuators to valves. Throughout this document, “actuator” can be understood as “actuator” or “combination of actuator with gearbox” providing a multi-turn or linear output. This document specifies: flange dimensions necessary for the attachment of actuators to industrial valves [see Figure 1 a)] or to intermediate supports [see Figure 1 b)]; those driving component dimensions of actuators which are necessary to attach them to the driven components; reference values for torque and thrust for flanges having the dimensions specified in this document.

This document specifies the requirements for the attachment of multi-turn actuators to valves. Throughout this document, “actuator” can be understood as “actuator” or “combination of actuator with gearbox” providing a multi-turn or linear output. This document specifies: flange dimensions necessary for the attachment of actuators to industrial valves [see Figure 1 a)] or to intermediate supports [see Figure 1 b)]; those driving component dimensions of actuators which are necessary to attach them to the driven components; reference values for torque and thrust for flanges having the dimensions specified in this document.

SIST EN ISO 5210:2026 is classified under the following ICS (International Classification for Standards) categories: 23.060.01 - Valves in general; 23.060.99 - Other valves. The ICS classification helps identify the subject area and facilitates finding related standards.

SIST EN ISO 5210:2026 has the following relationships with other standards: It is inter standard links to SIST EN ISO 5210:2023, SIST EN 13789:2011, SIST EN 12569:2020, SIST EN 1171:2003, SIST EN 1171:2015, SIST EN 13709:2011, SIST EN 13397:2002, SIST EN 14141:2013, SIST EN 1984:2011. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.

SIST EN ISO 5210:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.

Standards Content (Sample)


SLOVENSKI STANDARD
01-maj-2026
Nadomešča:
SIST EN ISO 5210:2023
Industrijski ventili - Priključki vrtilnih pogonov na ventilih (ISO 5210:2026)
Industrial valves - Multi-turn actuator attachments (ISO 5210:2026)
Industriearmaturen - Anschlüsse von Drehantrieben für Armaturen (ISO 5210:2026)
Robinetterie industrielle - Raccordement des actionneurs multitours (ISO 5210:2026)
Ta slovenski standard je istoveten z: EN ISO 5210:2026
ICS:
23.060.01 Ventili na splošno Valves in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 5210
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2026
EUROPÄISCHE NORM
ICS 23.060.99 Supersedes EN ISO 5210:2023
English Version
Industrial valves - Multi-turn actuator attachments (ISO
5210:2026)
Robinetterie industrielle - Raccordement des Industriearmaturen - Anschlüsse von Drehantrieben
actionneurs multitours (ISO 5210:2026) für Armaturen (ISO 5210:2026)
This European Standard was approved by CEN on 31 January 2026.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 5210:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 5210:2026) has been prepared by Technical Committee ISO/TC 153 "Valves" in
collaboration with Technical Committee CEN/TC 69 “Industrial valves” the secretariat of which is held
by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by August 2026, and conflicting national standards shall
be withdrawn at the latest by August 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 5210:2023.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 5210:2026 has been approved by CEN as EN ISO 5210:2026 without any modification.

International
Standard
ISO 5210
Fourth edition
Industrial valves — Multi-turn
2026-02
actuator attachments
Robinetterie industrielle — Raccordement des actionneurs
multitours
Reference number
ISO 5210:2026(en) © ISO 2026
ISO 5210:2026(en)
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 5210:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Maximum torques and thrusts . 2
5 Flange dimensions . 2
6 Designation . 4
7 Dimensions of driving and driven components . 4
7.1 General .4
7.2 Dimensions for assemblies capable of transmitting both torque and thrust: Group A .5
7.3 Dimensions for assemblies capable of transmitting torque only: Group B .6
7.4 Dimensions for assemblies capable of transmitting torque only: Group C.8
7.5 Dimensions for assemblies capable of transmitting torque only: Group D .9
7.6 Dimensions for assemblies capable of transmitting thrust only: Group linear actuators .9
Annex A (informative) Explanation of calculations .11
Annex B (normative) Dimensions of keys and keyways .13
Bibliography . 19

iii
ISO 5210:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 153, Valves, in collaboration with the European
Committee for Standardization (CEN) Technical Committee CEN/TC 69, Industrial valves, in accordance with
the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 5210:2023), which has been technically
revised.
The main changes are as follows:
— Figure 2 and Table 2 were updated for through bolting;
— output drive group B were clarified and updated;
— editorial changes were made.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO 5210:2026(en)
Introduction
The purpose of this document is to establish certain basic requirements for the attachment of multi-turn
actuators, in order to define the interface between actuator and valve.
This document is, in general, considered in conjunction with the specific requirements which may be agreed
between the parties concerned.
NOTE 1 In this document, the term “valve” can also be understood to include “valve with an intermediate support”
[see Figure 1 b)].
NOTE 2 When a combination of a multi-turn actuator and separate multi-turn/linear gearbox is coupled to form an
actuator, the multi-turn attachment to the gearbox is in accordance with this document [see Figures 1 c) and 1 d)]. A
combination of a multi-turn actuator with integral multi-turn/linear gearbox supplied as an actuator is in accordance
with Figures 1 a) and 1 b).
a) Direct interface b) Intermediate support c) Direct interface d) Intermediate support
interface (when combination of interface (when combi-
a multi-turn actuator nation of a multi-turn ac-
and multi-turn/linear tuator and a multi-turn/
gearbox) linear gearbox)
Key
1 multi-turn/linear actuator
2 interface (see this document)
3 valve
4 intermediate support
5 gearbox
6 interface (see this document)
7 multi-turn actuator
Figure 1 — Interface between multi-turn/linear actuator and valve

v
International Standard ISO 5210:2026(en)
Industrial valves — Multi-turn actuator attachments
1 Scope
This document specifies the requirements for the attachment of multi-turn actuators to valves.
Throughout this document, “actuator” can be understood as “actuator” or “combination of actuator with
gearbox” providing a multi-turn or linear output.
This document specifies:
— flange dimensions necessary for the attachment of actuators to industrial valves [see Figure 1 a)] or to
intermediate supports [see Figure 1 b)];
— those driving component dimensions of actuators which are necessary to attach them to the driven
components;
— reference values for torque and thrust for flanges having the dimensions specified in this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 273, Fasteners — Clearance holes for bolts and screws
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
actuator
device designed for attachment to a general-purpose industrial valve in order to provide for the operation of
the valve
Note 1 to entry: The device is designed to operate using motive energy which can be electrical, pneumatic, hydraulic,
manual, etc., or a combination of these. Movement is limited by travel, torque (3.4) or thrust (3.5) or combination of
both.
3.2
multi-turn actuator
actuator (3.1) which transmits torque (3.4) to the valve for at least one revolution and may be capable of
withstanding thrust (3.5)
Note 1 to entry: An actuator can be a combination of a multi-turn actuator and multi-turn gearbox.

ISO 5210:2026(en)
3.3
linear actuator
actuator (3.1) which transmits thrust (3.5) to the valve for a defined linear stroke
Note 1 to entry: An actuator can be a combination of a multi-turn actuator (3.2) and linear gearbox.
3.4
torque
turning moment transmitted through the mounting flanges and couplings
Note 1 to entry: Torque is expressed in newton-metres (N·m).
3.5
thrust
axial force transmitted through the mounting flanges and couplings
Note 1 to entry: Thrust is expressed in kilonewtons (kN).
4 Maximum torques and thrusts
The torque and thrust shall comply with the values listed in Table 1 which represent the maximum torques
and thrusts which can be transmitted simultaneously through the mounting flanges and couplings. They are
based upon specified criteria.
Table 1 — Maximum torque and thrust values
Torque Thrust
Flange type
[N·m] [kN]
F05 20 10
F07 40 20
F10 100 40
F12 250 70
F14 400 100
F16 700 150
F25 1 200 200
F30 2 500 325
F35 5 000 700
F40 10 000 1 100
F48 20 000 2 000
F60 40 000 4 000
The values specified in Table 1 have been defined on the basis of bolts in tension at a stress of 290 MPa and
a coefficient of friction of 0,2 between the mounting interface. All variations in these defined parameters
lead to variations of the transmittable torque or thrust or combination of both values. See Annex A for an
explanation of the calculation method.
The selection of flange size for a particular application should take account of additional combination of
torques and thrust that may be generated at the valve stem because of sizing, safety factors, inertia or other
similar factors. Specifically, the torque and thrust generated at the maximum output torque and thrust of
the selected actuator shall be calculated and considered in the selection of the flange along with the ability
of the valve and actuator to withstand such torque and thrust forces.
5 Flange dimensions
Flanges for actuator attachment shall comply with the dimensions shown in Figure 2 and given in Table 2.
The method of attachment shall be by means of studs or through bolting.

ISO 5210:2026(en)
Holes for the studs/bolts shall be positioned off-centre (see Figure 3 and Table 3), shall be equi-spaced and
shall conform to the requirements of ISO 273.
The interface on the valve shall have a recess corresponding to the diameter d . A spigot on the actuator is
optional.
The minimum values for dimension h shown in Table 2 apply to flanges having material of proof stress
R ≥ 200 MPa. The minimum values for dimension h applied to flanges having materials of proof stress
e 2
R ≤ 200 MPa shall be agreed between manufacturer and purchaser. The minimum values for dimension h
e 3
shall be at least 1 × d .
Dimension d has been based on providing sufficient landing for the nuts and bolt heads where applicable.
Such landing is defined as a radius from the bolt hole centre with the dimension (d − d ) / 2 and is a
1 3
minimum. The flange shape of both valve and actuator outside these areas of landing is left to the discretion
of the manufacturer.
The dimensions and bolting material are based on bolts in tension at a maximum stress of 290 MPa. On
agreement, between the manufacturer/supplier and purchaser, bolting material with different tensile
strength can be used, with no dimensional changes but with potential variation of the transmittable torque
and thrust value.
Figure 2 — Flange dimensions
Table 2 — Flange dimensions
Dimensions in millimetres
Dimensions Number of
studs or
Flange
c d
d h h h h h
1 a b 1 2 3 4 5 bolts
type
d d d d
2 3 4 5
min. max. min. min. min. min.
n
F05 ∅65 ∅35 ∅50 M6 ∅6,6 3 9 6 6 6 4
F07 ∅90 ∅55 ∅70 M8 ∅9 3 12 8 8 8 4
F10 ∅125 ∅70 ∅102 M10 ∅11 3 15 10 10 10 4
F12 ∅150 ∅85 ∅125 M12 ∅13,5 3 18 12 14 12 4
F14 ∅175 ∅100 ∅140 M16 ∅17,5 4 24 16 18 16 4
F16 ∅210 ∅130 ∅165 M20 ∅22 5 30 20 22 20 4
F25 ∅300 ∅200 ∅254 M16 ∅17,5 5 24 16 18 16 8
F30 ∅350 ∅230 ∅298 M20 ∅22 5 30 20 22 20 8
a
d shall be manufactured within the diameter tolerance f8.
b
d clearance holes for bolts and screws according to ISO 273 (medium as a recommendation).
c
h based on ISO 4033 – Hexagon high nuts (style 2).
d
h based on 1,0x d .
5 4
ISO 5210:2026(en)
TTabablele 2 2 ((ccoonnttiinnueuedd))
Dimensions Number of
studs or
Flange
c d
d h h h h h
1 1 2 3 4 5 bolts
type a b
d d d d
2 3 4 5
min. max. min. min. min. min.
n
F35 ∅415 ∅260 ∅356 M30 ∅33 5 45 30 30 30 8
F40 ∅475 ∅300 ∅406 M36 ∅39 8 54 36 36 36 8
F48 ∅560 ∅370 ∅483 M36 ∅39 8 54 36 36 36 12
F60 ∅686 ∅470 ∅603 M36 ∅39 8 54 36 36 36 20
a
d shall be manufactured within the diameter tolerance f8.
b
d clearance holes for bolts and screws according to ISO 273 (medium as a recommendation).
c
h based on ISO 4033 – Hexagon high nuts (style 2).
d
h based on 1,0x d .
5 4
Figure 3 — Positions of the holes for the studs/bolts
Table 3 — Positions of holes
Flange type α/2
F05 to F16 45 °
F25 to F40 22,5 °
F48 15 °
F60 9 °
6 Designation
Flanges are designated by flange type according to Table 1.
7 Dimensions of driving and driven components
7.1 General
The dimensions of the driving and driven components shall comply with the dimensions given in Tables 4 to
8.
ISO 5210:2026(en)
The depth of engagement of the valve-driven component into the actuator drive component and the
surface area of contact between the faces of the actuator drive component and the faces of the valve-driven
component should be considered to ensure that the stresses caused by contact do not exceed the capability
of the component materials. In some cases it can be necessary to use materials with superior mechanical
properties and/or to reduce the output torque of the actuator.
7.2 Dimensions for assemblies capable of transmitting both torque and thrust: Group A
Dimensions for assemblies of group A shall be as shown in Figure 4 and Figure 5 and given in Table 4
...

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